In the circuit shown in Fig., $${e_g}\left( t \right) = 2.5t$$ volts. What are the values of $$i(t)$$ and $${V_L}\left( t \right)$$ at $$t=4$$ seconds?

Two identical coils of negligible resistance when connected in series across a $$200V,$$ $$50$$ $$Hz$$ source draws, a current of $$10$$ $$A.$$ When the terminals of one of the coils are reversed, then current drawn is $$8$$ $$A.$$ The coefficient of coupling between the two coils is

For the two port network shown in Fig. the admittance matrix is

In the circuit shown in fig. For measuring resistance $$'R'$$ if the ammeter indicates $$1$$ $$A$$ and the voltmeter indicate $$100V$$, then the value of $$R$$ is ___________ Ohms and the error in measurement using the ratio $$V/$$$${\rm I}$$ is ________%